Hitherto, there has been proposed an electromagnetic pump of this type, including: a piston; an electromagnetic portion that attracts a plunger to a core using an electromagnetic force to move the piston forward; a spring that applies an urging force that is opposite in direction to the electromagnetic force to move the piston in reverse; an end plate that supports the spring; a suction check valve built in the end plate; and a discharge check valve built in the piston (see Patent Document 1, for example). In the electromagnetic pump, the electromagnetic portion is energized and de-energized to move the piston back and forth to suction working oil via the suction check valve and discharge the suctioned working oil via the discharge check valve.